EPA SDWIS ยท Del Norte County, California ยท 95 providers profiled
Del Norte County, CA Water Quality Report
Del Norte County is served by 95 major public water systems on file with the EPA.
Data current as of July 2026
๐Straight from EPA
๐งชReal Lab Results
๐ Updated Quarterly
๐ Local Expertise
Results for Del Norte County, CA
95 water providers on file for this county, sorted by population served.
Quick answer: Del Norte County has 95 water providers profiled, sorted by population served.
Lead Summary
Copper Summary
Magnesium
Calcium
Hardness, Total (ASCACO3)
Iron
Manganese
Copper, Free
Nitrate
Chromium, Hex
Totalhaloaceticacids (HAA5)
TTHM
Chloroform
Bromodichloromethane
Dibromochloromethane
Dichloroaceticacid
Trichloroaceticacid
Sodium
Gross Alpha Particle Activity
Gross Beta Particle Activity
Barium
Lead
Monobromoaceticacid
Turbidity
Odor
Violations on file
Coliform (TCR)
Older/archived health-based violation
Found at 3 of 95 providers
Surface Water Treatment Rule
Currently open health violation
Found at 5 of 95 providers
Lead And Copper Rule Revisions
Currently open health violation
Found at 5 of 95 providers
Revised Total Coliform Rule
Currently open health violation
Found at 1 of 95 providers
Contaminants found
Metals
Naturally occurring or corrosion-related elements, e.g. lead, arsenic, copper
Lead Summary
Detected: 0.0155 mg/L (ppm)
Found at 25 providers
Copper Summary
Detected: 3.6 mg/L (ppm)
Found at 8 providers
Iron
Detected: 4700 UG/L (ppb)
2/26/2025
Mostly an aesthetic issue (metallic taste, staining) rather than a health concern at typical levels.
Manganese
Detected: 140 UG/L (ppb)
2/26/2025
Mainly a taste/staining concern at typical levels; long-term neurological research at high chronic exposure is ongoing.
Copper, Free
Detected: 1600 UG/L (ppb)
Found at 6 providers
Chromium, Hex
Detected: 15 UG/L (ppb)
Found at 4 providers
Barium
Detected: 6.6 UG/L (ppb)
7/2/2025
Lead
Detected: 11 UG/L (ppb)
Found at 4 providers
A metal that can leach from old pipes, solder, and fixtures. Current medical guidance holds there is no truly safe level of lead exposure, especially for children and pregnant women.
Disinfection Byproducts
Formed when chlorine used to disinfect water reacts with organic matter
Totalhaloaceticacids (HAA5)
Detected: 8.4 UG/L (ppb)
Found at 2 providers
TTHM
Detected: 17 UG/L (ppb)
Found at 6 providers
A group of disinfection byproducts formed when chlorine reacts with organic matter. Long-term exposure above the legal limit has been linked to increased cancer risk in some studies.
Chloroform
Detected: 10 UG/L (ppb)
Found at 6 providers
One of the individual trihalomethane disinfection byproducts, formed when chlorine reacts with organic matter.
Bromodichloromethane
Detected: 4.5 UG/L (ppb)
Found at 6 providers
Dibromochloromethane
Detected: 2.2 UG/L (ppb)
Found at 5 providers
Inorganics
Common dissolved minerals and salts, e.g. nitrate, fluoride, chloride
Nitrate
Detected: 4.1 MG/L (ppm)
Found at 11 providers
Commonly from agricultural fertilizer runoff or septic systems. Above the legal limit, it's an immediate concern especially for infants.
Minerals
Everyday minerals that mainly affect taste and water hardness
Magnesium
Detected: 11 MG/L (ppm)
Found at 2 providers
Calcium
Detected: 23 MG/L (ppm)
Found at 2 providers
Sodium
Detected: 2.3 MG/L (ppm)
7/2/2025
Properties
General water characteristics like pH, hardness, and cloudiness (turbidity)
Hardness, Total (ASCACO3)
Detected: 68 MG/L (ppm)
Found at 2 providers
Gross Alpha Particle Activity
Detected: 1.98 PCI/L
7/2/2025
Other
Additional substances tested that don't fit neatly into the categories above
Dichloroaceticacid
Detected: 3.9 UG/L (ppb)
Found at 6 providers
Trichloroaceticacid
Detected: 4.8 UG/L (ppb)
Found at 6 providers
Gross Beta Particle Activity
Detected: 2.33 PCI/L
7/2/2025
Monobromoaceticacid
Detected: 1 UG/L (ppb)
6/3/2025
Turbidity
Detected: 0.14 NTU
5/5/2025
A measure of water cloudiness from suspended particles.
Odor
Detected: 1 TON
5/5/2025
Filtration considerations: General system types, not a specific product recommendation.